package com.shu.mmall.common;

import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import lombok.extern.slf4j.Slf4j;

import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;

/**
 * @author shujinhao
 */
@Slf4j
public class TokenCache {
    private static final String NULL="null";
    /**
     * token前缀
     */
    public static final String TOKEN_PREFIX="token_";

    /**
     * LRU算法
     */
    private static LoadingCache<String,String> localCache= CacheBuilder.newBuilder().initialCapacity(1000).maximumSize(10000).expireAfterAccess(12,TimeUnit.HOURS)
            .build(new CacheLoader<String, String>() {
                //默认的数据加载实现，当调用get取值的时候，如果key没有对应的值，就调用这个方法进行加载
                @Override
                public String load(String s) {
                    return "null";
                }
            });

    public static void setKey(String key,String value){
        localCache.put(key,value);
    }

    public static String getKey(String key){
        String value;
        try {
            value=localCache.get(key);
            if (NULL.equals(value)){
                return null;
            }
            return value;
        } catch (ExecutionException e) {
            log.error("localCache get error",e);
        }
        return null;
    }
}
